I don't think you will have a lesser experience in 2D, but I believe the majority opinion is that this is 3D done right. It's not used obnoxiously, if that makes any sense. I don't wanna get too into the movie, but I imagine it would be enjoyable either way.

The friend that saw it said he thought the 3d was very environmental, rather than a gimmick. It enhanced the movie but wasn't in your face, similar to Avatar. Gave everything more depth, more of a feeling that you're part of the action.